Expatriate health insurance customers should maintain a healthy diet to reduce their risk of contracting cancer.
Dr Mark Matfield, scientific coordinator at the Association for International Cancer Research, argued between one-third and half of all cases of this disease are "associated with diet, lifestyle or other environmental factors".
These can include excessive alcohol consumption and obesity, with "informed speculation" indicating that, as men are more likely to be affected by these risk factors, they have a higher chance of suffering from this illness than women, he said.
However, this hypothesis is not based on "experimental evidence", Dr Matfield admitted.
According to charity Cancer Research UK, evidence indicates excess bodyweight can be a factor in being affected by a range of cancers, such as those in the colon, gallbladder, pancreas, kidney and oesophagus.
Furthermore, cancers in the mouth, liver, bowels and larynx are correlated with alcohol consumption, whereas smoking is estimated to account for around three-quarters of all upper aerodigestive cancers in developed countries.